COVID-19 Vaccination–Related Pericarditis: A Korean Nationwide Study

Objective To investigate the incidence, characteristics, and outcomes of COVID-19 vaccine–related pericarditis (VRP) without myocarditis, we analyzed nationwide Korean data. Patients and Methods This is a retrospective nationwide report including all vaccinated Koreans with COVID-19 vaccine of any platform (BNT162b2, mRNA-1273, ChAdOx1, or Ad26.COV2.S) from February 26 to December 31, 2021. We analyzed the confirmed cases of COVID-19 VRP by the Expert Adjudication Committee. The incidence, clinical characteristics, and outcomes of COVID-19 VRP were analyzed. Results Among 44,322,068 Koreans with least one dose of COVID-19 vaccination, COVID-19 VRP was confirmed in 179 cases, with 1.73 per million shots (95% CI, 1.48 to 2.00 per million shots). The incidence of VRP was significantly higher in males than females (2.01 per 1 million doses vs 1.45 per 1 million doses, respectively; P=.029), in mRNA vaccines than in other vaccines (2.09 per 1 million doses vs 0.36 per 1 million doses, respectively; P<.001), and in those younger than 40 years of age than those older than 40 years of age (3.52 per 1 million doses vs 0.89 per 1 million doses, respectively; P<.001). The incidence of VRP was highest in males between the ages of 12 and 17 years (7.38 per 1 million doses; 95% CI, 2.01 to 16.07). Although there was no case of mortality, hemodynamically significant pericardial effusion requiring pericardial drainage was noted in 10 cases (5.6%). Conclusion COVID-19 VRP was very rare and developed mainly in association with mRNA vaccines, especially in males younger than 40 years of age. The clinical course of VRP was excellent, and there were no cases of mortality. However, the development of hemodynamically significant pericardial effusion should be carefully monitored.